pvcreate
initializes
PhysicalVolume
for later use by the Logical Volume Manager (LVM). Each
PhysicalVolume
can be a disk partition, whole disk, meta device, or loopback file.
For DOS disk partitions, the partition id should be set to 0x8e using
fdisk(8), cfdisk(8),
or a equivalent. For
whole disk devices only
the partition table must be erased, which will effectively destroy all
data on that disk. This can be done by zeroing the first sector with:
dd if=/dev/zero of=PhysicalVolume bs=512 count=1
Continue with
vgcreate(8)
to create a new volume group on
PhysicalVolume,
or
vgextend(8)
to add
PhysicalVolume
to an existing volume group.
Force the creation without any confirmation. You can not recreate
(reinitialize) a physical volume belonging to an existing volume group.
In an emergency you can override this behaviour with -ff.
-u, --uuid uuid
Specify the uuid for the device.
Without this option, pvcreate generates a random uuid.
All of your physical volumes must have unique uuids.
You need to use this option before restoring a backup of LVM metadata
onto a replacement device - see vgcfgrestore(8).
-y, --yes
Answer yes to all questions.
-Z, --zero y/n
Whether or not the first 4 sectors (2048 bytes) of the device should be
wiped.
If this option is not given, the
default is to wipe these sectors unless either or both of the --restorefile
or --uuid options were specified.
NEW METADATA OPTIONS
LVM2 introduces a new format for storing metadata on disk.
This new format is more efficient and resilient than the format the
original version of LVM used and offers the advanced user greater
flexibility and control.
The new format may be selected on the command line with -M2 or by
setting format = "lvm2" in the global section of lvm.conf.
Each physical volume in the same volume group must use the same format, but
different volume groups on a machine may use different formats
simultaneously: the tools can handle both formats.
Additional formats can be added as shared libraries.
Additional tools for manipulating the locations and sizes of metadata areas
will be written in due course. Use the verbose/debug options on the tools
to see where the metadata areas are placed.
--metadatasize size
The approximate amount of space to be set aside for each metadata area.
(The size you specify may get rounded.)
--metadatacopies copies
The number of metadata areas to set aside on each PV. Currently
this can be 0, 1 or 2.
If set to 2, two copies of the volume group metadata
are held on the PV, one at the front of the PV and one at the end.
If set to 1 (the default), one copy is kept at the front of the PV
(starting in the 5th sector).
If set to 0, no copies are kept on this PV - you might wish to use this
with VGs containing large numbers of PVs. But if you do this and
then later use vgsplit you must ensure that each VG is still going
to have a suitable number of copies of the metadata after the split!
--restorefile file
In conjunction with --uuid, this extracts the location and size
of the data on the PV from the file (produced by vgcfgbackup)
and ensures that the metadata that the program produces is consistent
with the contents of the file i.e. the physical extents will be in
the same place and not get overwritten by new metadata. This provides
a mechanism to upgrade the metadata format or to add/remove metadata
areas. Use with care. See also vgconvert(8).
--labelsector sector
By default the PV is labelled with an LVM2 identifier in its second
sector (sector 1). This lets you use a different sector near the
start of the disk (between 0 and 3 inclusive - see LABEL_SCAN_SECTORS
in the source). Use with care.
--setphysicalvolumesize size
Overrides the automatically-detected size of the PV. Use with care.
Example
Initialize partition #4 on the third SCSI disk and the entire fifth
SCSI disk for later use by LVM:
